How to take money when selling rare goods at various points?

Question

Electronic commerce

The essence of the product is a universal subscription. Something like certificates for impressions (where there are a number of activities and you can choose any), but a narrower scope and not one-time.
There are about 7 centers in the city where they can be used.
How is money usually handled in such cases between the certificate seller, the owners of each center, and the certificate issuer itself?
I see the system like this: I receive money for a subscription from the user, the user comes to the center, uses it, a certain amount N is transferred to the account of this center in my system, which, say, is transferred to a real account once a week. This is quite convenient if sales go through my site. And if through these centers themselves or specialized stores?
I give them N such subscriptions, they sell them and then transfer money to me for each sold? Or do they pay for them in advance (but this is obviously inconvenient for them)? And then the scheme described above already starts to work?
A lot of hassle and movement of money back and forth, looks very uncomfortable.

Answer 1

It is not necessary to sell them to them (they may not agree). You can issue certificates to them and, after some time, find out from them how much they have sold (or find out in your system which ones have been activated). Take away unsold certificates or they are waiting in the wings.
You summarize debt obligations and find out who owes how much to whom.

Answer 2

Each certificate in the system must have a unique code that cannot be faked.
That. you will be able to track the sale of the certificate and the sale of goods by the certificate. Your system must be a guarantor (ala bank) of the execution of certificates.
In the case of the scheme described in one of the answers: Vasya must Katya-Katya must Pete-Petya must Vasya, I see one drawback. All of them must conclude an agreement among themselves, and must trust each other. That. when the system grows, it is very difficult to trust xs who from 1000 connected.
Better centralization. That. During the reporting period, you will see how many certificates were sold (for what denomination), and how many goods were bought (for what denomination), and you can calculate the difference in money, taking into account your commission. That. monthly you will only have to either demand a transfer from them, or transfer them. Those. no need for 2 simultaneous cash flows.